Power operated magazine fed screw driver



Jan. 7, 1958 E. H. sHAFF 2,818,893

PowER OPERATED MAGAZINE FED SCREW DRIVER Filed May 31, 1956 2 sheetS-shet 1 #filo/weg Jan. 7, 1958 E. H. sHAFF POWEROPERATED MAGAZINE FED SCREW DIRIVER 2 Sheets-Sheet 2 Filed May 31. 1956 INVENToRg. 15P/765% H. 5h@ ff BY 4 l m gv/' //omeq.

United States Patent POWER OPERATED MAGAZINE FED SCREW DRIVER Ernest H. Shah, Lake Worth, Fla., assigner to The Aro Equipment Corporation, a corporation of Ohio Application May 31, 1956, Serial No. 588,295 13 Claims. (Cl. 144-32) This invention relates to improvements in power operated magazine fed screw driver. The principal objects of this invention are:

First, to provide a practical power operated tool in the form of a magazine fed screw driver which will rapidly drive a screw by means of compressed air and automatically reload itself with succeeding screws from a magazine to repeat the screw driving operation.

Second, to provide an air operated screw driver in which the screws are fed or loaded successively into the tool from a storage magazine by means of yair pressure.

Third, to provide an air operated screw driver in which a single manual trigger or control will automatically etfect the loading of a screw into operative position, the advance of the screw driver bit and screw into operating position and rotation of the bit to drive the screw home.

Fourth, to provide a power operated screw driver having an axial extensible and rotatable bit driven through a clutch that automatically disengages the rotary driving power from the bit when the screw is completely driven into the work.

Fifth, to provide a novel form of magazine for an air operated screw driver which will hold a large supply of screws and which can be simply and rapidly loaded or charged with a supply of screws.

Sixth, to provide a novel form of driving clutch and bit advancing mechanism for an air operated screw driver having a minimum number of parts that are relatively easily assembled and which are effectively retained and guided to prevent misalignment and breakage of the parts.

Other objects and advantages of the invention will be apparent from a consideration of the following description and claims. The drawings, of which there are two sheets, illustrate a highly practical form of the screw driver and an example of a loading device for loading screws into the magazine of the tool.

Fig. l is a top plan view of the assembled screw driver.

Fig. 2 is a vertical longitudinal cross sectional view taken along the plane of the line 2-2 in Figs. 1 and 3 and illustrating the mechanism in retracted at rest position.

Fig. 3 is a fragmentary transverse cross sectional view taken along the plane of the line 3-3 in Fig. 2.

Fig. 4 is a fragmentary horizontal cross sectional view taken along the plane of the line 4-4 in Fig. 2 and illustrating the parts in advance screw driving position.

Fig. 5 is a fragmentary vertical lcross sectional view similar to Fig. 2 but illustrating the mechanism in advanced operative position.

Fig. 6 is a fragmentary screw driver.

Fig. 7 is a transverse cross sectional view taken along the plane of the line 7-7 in Fig. 5.

Fig. 8 is a transverse cross sectional view taken along the plane of the broken line 8--8 in Fig. 5.

Fig. 9 is a transverse cross sectional view taken along the plane of the line 9-9 in Fig. 5.

front elevational view of the Patented Jan. 7, 1958 Fig. 10 is a fragmentary cross sectional view through a loading device for loading screws into the magazine of the screw driver.

The screw driver comprises a body 1 having a generally cylindrical motor housing 2 formed on the top and a hollow grip 3 formed on the bottom and defining an air inlet chamber 4 adapted to be connected to a source of air pressure by means of a flexible hose and coupling 5. The forward or left end of the motor housing 2 as shown in the drawings is open and internally threaded as at 6 to receive a generally cylindrical extension 7. The outer end of the extension 7 has a tubular tool guide neck 8 mounted thereon, the neck being slotted as at 9 and provided with ears 10 that are drawn together by the bolt 11 to clamp the neck to the extension.

The interior of the motor housing 2 defines a cylindrical chamber 12 within which a tubular motor cylinder is mounted. The ends of the motor cylinder 13 are closed by circular end plates 14 having bearings 15 mounted therein for rotatably supporting the drive shaft 16 of a rotor 17. The interior of the motor cylinder 13 denes an eccentric motor chamber 18 that receives the rotor in eccentric relation. The rotor 17 is provided with vanes that are not illustrated as rotary air motors of this type are well known.

A valve housing 19 projecting into the inlet chamber 4 defines a Valve passage and port 2t) opening to the inlet chamber and closed by the slidable valve 2l. The stem 22 of the Valve is of reduced cross section adjacent to the valve and extends forwardly to a trigger like finger piece 23 located in front of the grip. The passage 20 cornmunicates through a passage 24 in the body with an annular inlet 25 to the motor chamber. The valve passage 20 also opens through a relatively restricted port 26 to a separate feed chamber 27 formed on the side of the body 2. Air exhaust from the motor chamber 1S is collected in an annular passage 28 around the motor cylinder and directed forwardly through the passages 29 and 30 to the rear end of the extension 7.

The front or left end of the rotor shaft 16 is splined or tlatted as at 31 to drivingly engage a drive plate 32. The plate 32 is connected by rivets 33 to the flange 34 on the rear end of a drive spindle 35. The rear or inner end of the cylindrical extension 7 carries a further bearing 36 rotatably supporting and centering the spindle 35.

The left or projecting outer end of the spindle 35 is splined or flatted as at 37 to axially slidably and nonrotatably drivingly engage a driving clutch part 38. The driving clutch 38 has a piston-like sliding engagement within the cylindrical extension 7 and is sealed thereto by a rubber O-ring 39. The exhaust passages 30 from the air motor thus open to the rear face of the pistonlike driving clutch part. The space behind the piston is vented to the atmosphere by a port 40 having less area than the passages 30.

Axially slidably and relatively rotatably sleeved around the attened end 37 of the drive spindle is a tubular driven spindle 41. The rear end of the spindle 41 projects into the outer face of the driving clutch part 38 and is axially retained therein as by the snap ring 42. Towards its forward end the driven spindle 41 is exteriorly threaded to receive the adjustable abutment nut 43 and forwardly of the nut is passed rotatably through a centering bearing 44 and a hardened supporting cup 45. A driven clutch part 46 is axially slidably mounted around the inner end of the driven spindle and locked against rotation relative to the spindle by the balls 47. The axially opposed faces of the driving clutch member 38 and the driven clutch member 46 as appears in Fig. 5 have coacting radially serrated clutch faces 48. A helical spring 49 of at stock is corn- Y pressed between the abutment nut 43 and the driven clutch part 46 to bias the clutch parts toward engaged driving position. i

The hardened centering cup 45 is slidable in both the cylindrical extension 7, andtthe guide neck 8 and a@ second helical spring 50 biasesl the cup 45 and through it. the driven spindle 41 rearwardly. A tool bit Slis.. threaded: into the leftk or: outer: end. ofthe drivenspindle. 41` and projects axially forwardly into-aguidebore Slimme-outerend of the guide neck. The bit Shhas, an outer tip 53 shapedI to coactwith the heads of the particular type et screws tobe driven by the mechanism.. The cuter or lett end of theguide necky Sideiines:averticallyV transverse passage 54.havingftlat sidewalls .and transversely intersecting the guide bore 52. Vertically slidablyrrmounted in the passagev 54 is al rectangular.- block-lil-:e'carriage 5S with an axially extending, bore 56 formed; through its upper portion totreceive thescrews to be'driven. The transversely extending-vholesy 57 areformedonly to lighten-thc carriage block and-do-notenter.into the operation-of the apparatus.

The carriageblockfSS` is supportedion its underside by aspring-arm Stltat.V extends rearwardly along thezunder.- sideoi the guide neck 8 andthe outer-endet theftubular extension? where it is curved laterally as at: S9 and'ex tendsrearwardly to an anchor dit (seevFig. 6') on' the lower side of the motor housing. T hespringxarm 58 has an'upwardly extendinglportion- 61 thatprojects upwardly through a slot 62 in the bottom of the guideneclcand'into the pathof. the hardened guidevcup lt' willtbus be seenthat advancing motion of. the guide cupto theleftf asV shown in Fig. 2 Wilkengage and displacethe upwardlyextending portionl` of the spring'arm and simultaneously displace the carriage-block Suntilthebore darin the carriage is aligned with the bore 52.1in the guideneck. ln. this positionof the carriage the tcolbit lcan,beprojected through the carriageto engage andfadvanceascrew from the carriage bore into the1work. Half round'screw4 retainingjaws 63am yieldably supportedin front of. the, left. end of the bore S2'by springablearmsedcsecured to thesides of the guide neck. to` temporarily andtyieldahly suppcrtthe screw being drivenuntil the-screwis advanced into the work. As appears mostl clearly inlig.` tetheV spring jaws 63 willopenoutwardly to passthe head of the screwy at the end of:thescrew.dritingoperation.

Screws are directed individually andisuccessively. to the bore 56m thecarriage blockbyI entering throught a ter,- ward holel 65 formed obliquely'in` the outer. er1-dict the guideA neck abovethe tool-guide-bore. The holehn registers Withthe rearv end'of the screw receiving bore 56 in thecarriageblock whenthe carriage-block is in retractedor raised position; The upper side of the carriage block has an extension-66 that blocks the feedlhole-whenthe carriage block is advanced'into registry with 'thetool' bore 52. ln order to prevent' more than one screw, at a time entering the bore 56 fromthe feedhcle ,65am angled' stop 67 is sccured'to the side of the guide neck and projected through a slot in the side of the carriage block to intercept the heads of screws entering the carriage block.

Screws are directed automatically` to the ieedhole 65 by afspiral tubular magazine 68 whichhasits yforwardend. 69 slidably and'removably.receivedin,the-feed hole. The magazineis wrapped in spaced relationshiparound the guide neck and the tubular extension '7'of the body in. order to provideincreasedv length and capacity inthe magazine and'to providesuicientspringability and easy disengagement of; the magazine` from the feed hole 65;. The rear. end'of the magazine 68 is received as at: 71Min. theprevicusly'described feed chamber 2??. Air; pressure; admittedto the magazine from-the feedechambei* 27 effectively blowstlle screws in tthe,magazinenintdthe boreiu. the; carriageblock.V ln; orden that there will.'v be; 11o-.re-Y sistance.. to. this. movementi of: the` air-'and screws. through; the magazine the extremeouter Vend: of; .theeguidexneeleiis :gewisse A 1 V provided with an exhaust port 71 registering with the retracted position ofthe bore 56. y

The magazine 68 is easily and quickly loaded or charged by means of a loading device such as is illustrated in Fig. 10. The loader consists of a supply tube 72 that may come from a manual or automatic screw orienting appara tus that directs screws successively and headlirst as at '73. The tubef72-.delivers1into-a nozzle 74 threaded into a jet chamber in the loadenblock; '75. Compressed air from the pipe 7 6 is admitted by the valve 77 to the jet chamber aroundv thernozzle andffunctions torapidly suck screws out of the nozzleeandthe'tube and'blow them-into'theoutlet passage 78:- Apin;79-coupled:to -the'valve 77 prevents accidental discharge of the screws. The loader block has a recess or socket-80 aligned'y with the outlet 78 and adapted to receive the front end of the magazine tube 68 that is applied to the loader for loading the magazine.

With-the magazine 6S-,charged1andwith the apparatus -in the .position shown-in Fig. 2 the operation-ofV the screw driver is as follows. Retraction of the trigger 23 and valvestem 22, irst` opens the valve 21 and admits air pressure to both the motor chamber 18 andthe inlet chamber 27. Th air motor starts to rotate and one screw is blown from the .magazine into thelbore 56 in the retracted carriage block. Continuedlretraction of the trigger 23fcauses-the enlargedportion 122-0f the valve stem to close oftT the air pressure from the magazine while continuing-the supply toithe motor. The exhaust from the motor chamber 18is directed through thepassages, 29 and 30 to the rear face of the driving clutch member'tA whichthus is movedI forwardly or advanced to the left while rotating with the` drive spindle` 3S. The drivingI clutchmember axially engages andadvances the driven spindle 41 and the tool bit-51.y and the spring 49 normally holds the clutch members 38 and 46vin engagement so both the driven spindle andithe toot bit rotate with the motor. The advancing spindle 41V carrieswith it the hardened cup 45 that engages and depresses the raised portion 61; ofthe springarm 58 so that the carriage block SS- is advancedtotits lower registeringl position with-the guide borevSZin time-for` theadvancingtip 53 of the bit to enter the bore 56 and pickup the screw in the carriage bore. As was previously explained the bit feeds the screw: outwardly through the yieldable holding jaws 62 and turns, the screw into the work. When the screw is completely seatedinthe work the resistance torotation of the tool b it and the driven spindle 41 will cause the clutch parts 38 and 46 to automatically disengage and ratchet over each?l other so theoperator will know when thevscrew'is fully seated. The compression in the spring 49 will-determine howtightly the. screws are tobe seated and-this compression can be adjusted by means of the nut 43.

Having thus described the invention, what is claimed as new andisdesired to `be secured by Letters Patent is:

1. A-1:i ower` operatedrmagazineffedscrew. driver comprising, a body forminggamotor housing and a grip, a.

cylindrical extension ,on saidbody coaxial withsaid motor:y

housing, a tool guide neck clamped to the end of and extending axially.- from saidA extension, an-` air motor in said housing having` ant axially lxed latted shaft extendingaxially into-said extension, an air inlet inV said gripiattrigger operatedinlet valve in said grip alording communication; betweensaidI inlet; and said motor, an. outlet passage formed in saidhousing'frorn said motor to theainner end' of said extensioni a; driving clutch part having a piston-like sliding itin; said extension and aL sliding; and rotary driving` connection. onV said shaft, a tool spindle having an axially slidable and relatively rotatableengagement with saidfshaft in front of said driving clutch part and abutted axially thereagainst, a snap'ringv axially retaining,- said. spindley in engagement with said driving clutchf part WhileA permittingmelative. rotations therebetween, `adrive,nclutch-.part having.relativelyaxially slidable and non-rotatable: drivingengagementt with said 1 spindle and opposed to said driving clutch part, an adjusting nut threaded on said spindle, a first spring bearing between said nut and said driven clutch part to bias said clutch parts together, said clutch parts having opposed axially facing radially serrated coacting clutch faces, a hardened bearing cup axially slidably positioned in said extension and slidable into said tool guide neck, a bearing carried by said cup and rotatably centering said spindle in said extension, a second spring positioned in said neck and biasing said bearing cup rearwardly, a tool bit threadingly engaged in the end of said spindle and having a screw driver tip, the end of said neck having a bore therein axially receiving said bit and further defining a transverse at sided passage intersecting said bore near the outer end thereof 'and ahead of the retracted position of the outer end of said bit, a screw feed carriage transversely slidably positioned in said passage and defining an axially extending bore adapted to be brought into registry with said bore in said neck, a spring arm supporting said carriage in said passage and extending along said neck and said extension to a connection to said body to bias said carriage and the bore therein out of registry with the -bore in the neck, said arm having a transverse offset projecting through a slot in said neck into the path of said bearing cup to be engaged by said bearing cup to move said arm and carriage and register the bore in the carriage with the bore in the neck, the outer end of said neck having a screw feed hole formed obliquely therein and opening to the bore in said carriage in the retracted position of the carriage, said passage having a projection therein extending into the bore in the carriage in the retracted position thereof to intercept and limit the entrance of one screw at a time into said carriage, said carriage having a portion blocking said screw feed hole in the advanced position of the carriage, laterally spreadably mounted screw retaining jaws at the outer end of said bore in said neck, a tubular spiral screw magazine having its outer end removably received in the rear end of the feed hole in said neck and having its rear end supported in a recess -in the side of said body, an air passage forme in said body and opened to said inlet by said valve and extending to the rear end of said magazine, and a cut-olf portion on said trigger valve arranged to block said last passage in the fully actuated position of said trigger, said body kdefining a restricted escape passage of smaller size than the outlet from the motor to behind said driving clutch part opening to the exterior of said body from behind said driving clutch part.

2. A power operated magazine fed screw driver cornprising, a body forming a motor housing and a grip, a cylindrical extension on said body -coaxial with said motor housing, a tool guide neck on the end of and extending axially from said extension, an air motor 1n said housing having an axially iixed ilatted shaft extending axially into said extension, an air inlet in said grip, a trigger operated inlet valve in said grip affording com- -munication between said inlet and said motor, an outlet passage formed in said housing from said motor to the inner end of said extension, a driving clutch part having a piston-like sliding t in said extension and a sliding and rotary driving connection on said shaft, a tool spindle having an axially :slidable and relatively rotatable engagement with said shaft in front of said driving yclutch part and abutted axially thereagainst, means axially retaining said spindle in engagement with said driving clutch part while permitting relative rotation therebetween, a driven clutch part having relatively axially slidable and non-rotatable driving engagement with said spindle and opposed to said driving clutch part, an adjusting nut threaded on said spindle, a first spring bearing between said nut and said driven clutch part to bias said clutch parts together, said clutch parts having opposed axially facing radially serrated coacting clutch faces, a bearing cup axially slidably positioned in said extension and slidable into said tool guide neck, a bearing carried by said spindle in `said exten- -cup and rotatably centering said in said neck and biassion, a second spring positioned ing said bearing cup rearwardly, a tool bit engaged in the end of said spindle and having a screw driver tip, the end of said neck having a bore therein axially receiving said bit and further defining a transverse flat sided passage intersecting said bore near the outer end thereof and ahead of the retracted :position of the outer end of said bit, a screw feed carriage transversely slidably positioned in said passage and defining an axially extending bore adapted to be brought into registry with said bore in said neck, a spring arm :supporting said carriage in said passage and extending along said neck and said extension to a Iconnection to said body to bias said carriage and the bore therein out of registry with the bore in the neck, said arm having a transverse offset projecting through a slot in said neck into the path of said bearing cup to be engaged by said bearing 'cup to move said arm andcarriage and register ythe bore in the carriage with the bore in the neck, the outer end of said neck having a screw feed hole formed obliquely therein and opening to the bore in said carriage in the retracted position of the carriage, said carriage having a portion blocking said screw feed hole in the advanced position of the carriage, a tubular spiral screw magazine having its outer end removably received in the rear end of the feed hole in said neck and having its rear end supported in a recess in the side of said body, an air passage formed in said body and opened to said inlet by said valve and extending to the rear end of said magazine, and a Vcutoi portion on said trigger valve arranged to block said last passage in the ful-ly actuated position of said trigger, said body dening a restricted escape passage of smaller size than the outlet from the motor to behind said driving clutch part opening to the `exterior of said body from behind said driving clutch part.

3. A power operated magazine fed screw driver comprising, a body forming a motor housing and a grip, a 4tubular extension on said body coaxial with said motor housing, a tool guide neck on the end of and extending axially from said extension, an air motor in said housing having an axially xed flatted shaft extending axially into said extension, an air inlet in said body, a trigger operated inlet valve in said body aording communication between said inlet and ysaid motor, an outlet passage formed in said housing from said Imotor to the inner end of said extension, a driving clutch part having a piston-like sliding fit in said extension and a sliding and rotary driving .connection on said shaft, a tool spindle having an axially slidable and relatively rotatable engagement with said shaft in front of said driving clutch part, means axially retaining said spindle in fixed axial relation with said driving clutch part Iwhile permitting relative rotation therebetween, a driven clutch par-t having relatively axially slidable and non-rotatable driving engagement with said spindle and opposed to said driving clutch part, a first spring bearing between said spindle and said driven lclutch part to bias said clutch parts together, said clutch parts having opposed axially facing radially serrated coacting clutch faces, a bearing cup axially slidably positioned in said extension and slidable into said tool guide neck, a bearing carried by said cup and rotatably ycentering `said spindle in said extension, a second spring positioned in said neck and biasing said bearing cup and spindle rearwardly, a tool bit engaged in the end of said spindle and having a screw driver tip, the end of said neck having a bore therein axially receiving said bit and further deiining a transverse passa-ge intersecting said bore near the outer end thereof and ahead of the retracted lposition of the outer end of said bit, a 'screw feed `carriage transversely slidably positioned in said passage and defining an axially extending bore adapted to be brought into registry with said bore in said neck, a spring arm supporting said carriage in said passagel and extending along said neck to asrssesf 7 awconnection Yto lsaid: body.' tor-bias.. said carriage and. the bore: therein: out .of said arm'.v having` ai transverse odset: projecting. through a. slot; in: said: neck; intoffthef pathf. of'said: bearing: cup to:V be engaged.. by. said bearing; cup= to: move said). arm

and: carriage. and register. r the bore-.a in .the carriage with' the bore inthe..neckytheaouter'endsoxsaidrneck having:`

a screw feed; hole formed. obliquelyithereini and; openfingto-the bore.. iusaidcarriage-A in the,l retracted position; carriage havingr af. portion blocking;

of the. carriage; said; said; screw feedholeinfthe:advaneedposition of the carriage,. ai ,tubulan'spiralz screw magazinerhaving its. outer end.- removably; received." in the: rear: end of! the; feed. hole4 in. said. neclo. and.t havingaits. rear: end) cess. init the: side of. said body; an; air said; body and openedtto saidinletr by saidvalve and extending toi-themrearendi or saidmagazine, and. a. cutoff portion on said: trigger valve arrangedito. block-1 said -lastpassage; in. thef, fullycactnateds` position.i ofa said. valve, said. body dfening size. thanthe outlet.fromthegmotor tolbehind; said driving'cl'utch part .openinggtoithe exteriorrof said; bodyfrom behind said driving clutclnpart.

4. A poweroperated magazineffedtscrew driver'comprising, abody forming a:motor.;ho.using. anda a: grip, a tubular extension on said/body.-projectingirornssaidfinosupported in a reytor housing, a tool guide neck. extendingnaxially. from.

said extension', an. motor insaid: housing having an axially xed.: shaft. extending. axially into; saidf extension,.

an air inlet` in: saidbody, aY manually,- operatediinletf valve in said body aiTordingzcommunication hetweenfsaids inlet:

and said motor, an outletpassage.:formedrinsaidhous ing from said motortozthe'innerend" of said. extension, sliding.' tf in:

a driving clutch` partel having; apiston-like said extension and.y a sliding..v and rotary: driving'. connecf tion on said shaft, aitooli spii1dle.l1aving;an' axially slidable. andk relatively rotatable; engagementl with; said' shaft in front of said driving clutch part,.meansaxially retaining; said spindle in xed axial relationwith' said: driving clutch part while: permitting relative rotation`-v there.- between a driven yclutch part: having relatively axially slidable and .nonfrotatable drivingyengagement with: said to said: driving clutch. part,l a; iirsti springbearing. betweensaid spindle; and' said: driven clutch part tobias saidzclutchv parts/together,saidfclutch parts, serrated* coacting positioned in 'said extension andi rotatably centering. said: spindle in said; in. said' neck and. biasing: said bearingand spindle rearwardly, a tool bit. spindle.y and: having a; screw.rv `said neck having.. a bore therein;

spindle and opposedv havingy opposed axially facing c radially clutch faces, aV bearing axially lslidably extension, ar second: spring positioned;

engaged in the end of said. driver tip, the end: of

axially receiving. said bitY and further dening awtransverse passage intersecting lsaidzbore nearxthe. outer end;

thereof and aheadl of the. retracted position of theouter end ofsaid'-bit,. a screw. feedcarriage transversely slidably positioned.insaidpassage.: andidetining an. axially.

extending bore adapted` ito .ble brought into` registry. with said'bore in said'neck,

aspring armzsupporting said `carriage in-'said passage .-andextending along said neck. tov

a connection to said body to bias said'carriage and! the bore therein out' of registryxwiththe. bore in the: neck, said arm` having. a. 'transverse offset.' projecting through a slot insaid` neck into-the path ofy said bearingto be. engaged by saidbearing tomoveusaid` arm and carriage andregister the-.bore inthe 'carriage with the. bore in the neck, thel outer end of Vsaid neck having a screw feed hole formed obliquely therein and opening to the bore in. said carriage inthe retractedy position of the carriage, a. tubular spiral screwmagazinel having' its removably received in @the rear end ofthe feed hole in said neck. andlhaving; its rearaend..supported; in a. recess in. the. side of saidljody; Van:v ain hody andopened.ztorsaidiinletrby said valve :'andiextending totfreanendfof saidfmagazine. and'sa cutfoi portiony registry. with L the: bore: in the neck,

jnrssa-geA formed in' af restricted. escape -passageof smaller outer. endl passage; formed f in: said.-

-. an axially extending bore, adapted..

`8 ontsaid valve arrangeditcnblock;saidilasty passage inrthefully. actuatedzposition oisaidrvalve..

5:.. A'1 .power-:operatedlnragazineffedfscrew driverzcom.- prising,^, a body. forming-.al` motorl housingxand*l a:.gri\-p., al; tubularfextension; having; an: outer neck. on saidI body, .any air motor in.Y saidhousing; havinggaa shaft extending. intoA said extension, yanfzailz inlet. in -saidi body, a` triggerv operated. inlet: valve on sai-.dy body in: cooperative position relative,- to. saidl grip.- aiording..communication between` said inlet. and' said.- moton. an, outletrpassageJiorrned.- in said; housing fro-rnr said;motor to the..l inner'- endof s aid. extension, a piston. slidingly; mountedinsaid extension. andy rotatably drivingly connected. to `said shatt,; atool ybitl slidably androtatablyl guidedinssaid neck, means'axially. drivingly connecting saidfl piston. to. said bit, means in cludingA said piston formingga. yieldingly disengageable automatic clutchl connectionbetween said shaft and said bit, a springl positioned. in*` said. neck and. biasing; said.` bitj rearwardly, the end `Of'said;.neek having; a. bore thereinaxially receiving saidL bit and.. further.. dening a transf. verse at .sided passage. intersecting. saidv bore. near. the outer end thereof andwahead .of theretracted position. of. tlie. outer. endV of said. bit,. a,V screw. feed, carriage transversely. slidably positioned in. said-passager and defining` to be. brought into registry with said bore. insaid. neck, aspring arm sup.- porting. said carriagein said passage and extendingyalong.. said neck and said extensionrto.. a connectiontosaidbody to biassaid carriage and the bore therein outof registry with the. bore in the neck, saidr arm h'avingua` transverse offset projectingthrough a slot. in. said' neckinto. the path of a projection on said bit to. be engaged thereby tomove. said arm .and carriage and'register th'e bore in the carriage witlitlie bore in th'e neck, the outer end ofsaid neck having a screw fed'li'ole-formed obliquely therein and opening to the bore' in said' carriage in the retracted" position ofthe carriage, saidpassage having a projection. therein extending into the bore in the carriage in' the retracted position thereof' to intercept'and'limit the entrance;v of onescrew at a time-into saidcarriage,A said carriage. having a portion blocking saidscrewfeed hol'e' in' the advanced position olf-"the carriage; laterally'spread'ably mounted screw retaining jaws at th'e'outer end of said' bore' in saidneck; a tubular-.spiraliscrewv magazine having'itse outer endremovablyreceivedin' therearl ende-of' thef -feed hole in said'neck and"havingits'rear-end supported inral recess in the side' of saidbody, an'ainpassage'formedinJ said body' andA opened tosaid inletby' said-i valve and`l-ex tending to the rear end osaidi magazine; andawutoit? portion on'said'valve arrangedfto blocksaidl'ast passage in the fully actuated-position of;l said valve; saidbod'y.i ldeiining4 a restricted escapef'pa'ssage' oismaller'size/ than the outlety from` the motor -to-behind said driving-'clutch part openingy to the exterior ofsaid body. from behind said drivingfclutch3 part: Y

6. A power operatedmagazine fedscrewfdriverconr-A prising, a body formingI amotor housingy and a-.gripgV a tubular extensionhaving anouter neckon= saidlbody; am air motor in saidl housing having-a shaftI extending `axially into said'extension, an-'air-inlet in saidbody, an-inlet'valvex on said body incooperative position relative-to saidi grip= affording communicationbetween said'. inlet andi said motor, an outletl passage formedf in said housingf from saidmotor to the inner endofsaid extension,y a piston'I slidingly-mountedinfsaidzextension, Ia toolbit-slidably andi rotatably guided in` said neck. andl having al slidingY and: rotary driving connection to: said shaft, meansV axially drivingly connectingy said piston tosaid bit, a spring positioned' in said neckandr`biasing.; said. bit rearwardly, the end of saidfneckhaving a bore therein axially receivingf said bitV and furtherfdeiining a transverse passage inter-- secting said bore near-rthefouter endthereofandiaheadl-ofi the retracted :position: oi thelouter: end of saidibit, awscrew` feed carriage transversely slidablyfpositioned insaid; ypas sageanddetningantaxiailyiextending boreadaptedttobef brought intotregistry .witlrY saidf boreinssaid-"neclr, aspring arm supporting said carriage in said passage and extending along said neck to a connection to said body to bias said carriage and the bore therein out of registry with the bore in the neck, said arm having a transverse offset projecting through a slot in said neck into the path of a projection on said bit to be engaged thereby to move said arm and carriage and register the bore in the carriage with the bore in the neck, the outer end of said neck having a screw feed hole formed therein and opening to the bore in said carriage in the retracted position of the carriage, laterally spreadably mounted screw retaining jaws at the outer end of said bore in said neck, a tubular spiral screw magazine having its outer end removably received in the rear end of the feed hole in said neck and having its rear end supported in a recess in the side of said body, an air passage for-med in said body and opened to said inlet by said valve and extending to the rear end of said magazine, and a cut-off portion on said valve arranged to block said last passage in the vfully actuated position of said valve.

7. In an air operated screw driver having a body with a neck and a grip, said neck dening bore for a tool bit and a transverse passage intersecting said bore adjacent the outer end thereof, an air motor in said body, a tool bit rotatable and slidable in said bore between an extended position and a retracted position inwardly of said passage, means including an automatically disengageable clutch drivingly connecting said motor to said bit, piston means in said body connected to said bit to advance the same, spring means connected to retract said bit, an air inlet passage having a manually operable valve therein formed in said body and opening to said motor, an outlet passage formed in said body from said motor to said piston means to advance said bit, a screw feed carriage block slidable in said transverse passage and having a bore formed therein adapted to be advanced with the block into registry with the bore in said neck, a spring arm supporting said block and swingably connected to said body, a transverse off-set in said arm, a projection on said bit reciprocable therewith to engage said off-set to advance said block, a feed hole formed in said neck and and registering with the retracted position of the inner end of the bore in said block, a tubular spiral magazine wrapped around said neck and having its front end removably received in said feed hole to deliver thereto, the rear end of said magazine being received in said body, a feed passage formed in said body from said inlet to said magazine, and valve means opened momentarily upon opening said rst valve positioned to control said feed passage.

8. In an air operated screw driver having a body with 'a neck and a grip, said neck defining bore for a tool bit and a transverse passage intersecting said bore adjacent the outerend thereof, a tool bit rotatable and slidable in said bore between an extended position and a retracted position inwardly of said passage, a motor in said body, means drivingly connecting said motor to said bit, piston means in said body connected to said bit to advance the same, spring means connected to retract said bit, an air inlet passage having a manually operable valve therein formed in said body and opening to said motor, an outlet passage formed in said body from said motor to said piston means to advance said bit, a screw feed carriage block slidable in said transverse passage and having a bore formed therein adapted to be advanced with the block into registry with the bore in said neck, an arm supporting said block and swingably connected to said body, a transverse olf-set in said arm, a projection on said bit reciprocable therewith to engage said off-set to advance said block, a feed hole formed in said neck and registering with the retracted position of the bore in said block, a tubular spiral magazine wrapped around said neck and having its front end received in said feed hole to deliver thereto, the rear end of said magazine being received in said body, a feed passage formed in said body from said inlet to said magazine, and valve means trol said feed passage.

9. In an air operated screw driver having a body with a neck and a grip, said neck dening bore for a tool bit and a transverse passage intersecting said bore adjacent the outer end thereof, a tool bit rotatable and slidable in said bore between an extended position and a retracted position inwardly of said passage, a motor in said body, means drivingly connecting said motor to said bit, piston means in said body connected to said bit to advance the same, spring means connected to retract said bit, an air inlet passage having a manually operable valve therein formed in said body and opening to said motor, a passage formed in said body from said inlet passage to said piston means to advance said bit, a screw feed carriage block slidable in said transverse passage and having a bore formed therein adapted to be advanced with the block into registry with the bore in said neck, an arm supporting said block and swingably connected to said body, a transverse off-set in said arm, a projection on said bit reciprocable therewith to engage said off-set to advance said block, a feed hole formed in said neck and registering with the retracted position of the bore in said block, a tubular spiral magazine wrapped around said neck and having its front end received in said feed hole to deliver thereto, the rear end of said magazine being received in said body, a feed passage formed in said body from said inlet to said magazine, and valve means positioned to control said feed passage.

l0. In an air operated screw driver having a body with a neck and a grip, said neck defining bore for a tool bit and a transverse passage intersecting said bore adjacent the outer end thereof, a tool bit rotatable and slidable in said bore between an extended position and a retracted position inwardly of said passage, a motor in said body, means drivingly connecting said motor to said bit, piston means in said body in thrust transmitting relation to said bit to advance the same independently of said motor, spring means connected to retract said bit, an air inlet passage having a manually operable valve therein formed in said body and opening to said motor, a passage formed in said body from said inlet passage to said piston means to advance said bit, a screw feed carriage block slidable in said transverse passage and having a bore formed therein adapted to be advanced with the block into registry with the bore in said neck, means supporting said block and swingably connected to said body, coacting camming projections on said bit and said supporting means engageable in the advanced position of said bit to advance said block, a feed hole formed in said neck and registering with the retracted position of the bore in said block, a tubular spiral magazine wrapped around said neck and having its front end received in said feed hole to deliver thereto, the rear end of said magazine being received in said body, a feed passage formed in said body from said inlet to said magazine, and valve means operable with said first valve positioned to control said feed passage.

11. In an air operated screw driver having a body with a neck and a grip, said neck defining bore for a tool bit and a transverse passage intersecting said bore adjacent the outer end thereof, a tool bit rotatable and slidable in said bore between an extended position and a retracted position inwardly of said passage, a motor in said body, means drivingly connecting said motor to said bit, piston means in said body in thrust transmitting relation to said bit to advance the same, spring means connected to retract said bit, an air inlet passage having a manually operable valve therein formed in said body and opening to said motor, a passage formed in said body from said inlet passage to said piston means to advance said bit, a screw feed `carriage block slidable in said transverse passage and having a bore formed therein adapted to be advanced with the block into registry with the bore in said neck, means supporting said block and swingably connected to said body, coacting camming projections on said bit and positioned to consaidL supporting. means engageable., inthe, advanced posiwrapped around said neck and havingl its front end received. in` saidnfeed; hole. todeliver thereto, therear end` of. said` magazine being', received in said body, a feed passage: formedin, saidy body from said inlet toV said magazine; and, valve, means positioned to control saidfeed passage.

1.2. Anairoperated screw driver. comprising a body with. argrip, a necks, on` the end. of saidl'body, said neck deningbore for aftool bit and a transverse passage interseating, said bore adjacent' the outer end thereof', an air motor in, said body, a tool bit rotatable in said bore, means for. relatively. reciprocatingV said neck and bit betweenv an extended-positionA and a retracted position of theA bitinwardlyof said passage.,` meansdrivingly connectinghsaidrmotor to said bit, an air inlet passage having a= manually operable valve therein` formed in said' body andA openingto said motor, a passage formed in said body from, said inletv passage to saidtreciprocating means to relatively advance said. bit,ascrew feed, carriage block slidable in said transverse passage and having a bore formed therein@ adapted to bef .advancedv with the block intoregistryV Withthe bore, in said neck,tmeans supporting saidtbloclefor swinging motion4 relative tosaid bodytransversely. in said transverse passage, coactingcamming pro-V jections on said bit and said supporting means engageable in. the advanced position of said bit to advance saidblock, ai feedA hole formed in said neck. and registeringwith the retracted. position of the` bore in said, block, a tubular.

spiral magazine wrapped around, said neck, and having its; front endreceivedy insaidfeed hole todeliver thereto,

the bore in, said block, a. tubular spiral magazine the rearrend of said magazine being received in said body, a feed'passage.'formed'in saidv body from said inlet to saidmagazine, andrvalve means positionedtol control said feed passage.

ll3 Anair operated screw driver comprising a body withV a grip,l a neck on the end of said' body,v said neck definingV aborefor a tool bit andafeed hole intersecting tlie bore, an Vair motor in said body, av tool bit rotatable in saidb'ore, means for relatively. reciprocating said neck and bit between an extended position and a retracted position of the bit inwardly of'said'feed hole, meansdrivingly connectingsaid motor to said bit, an air inlet passage having, atmanually operable valve therein formed in. said'body andopening tosaidmotor, a passage formed in saidbody from said` inlet passage to said bit reciprocatingmeans, a feed holeformed in said neck and opening to the boreinsaidnecha tubular. spiral magazine wrapped y 'front end. received in.

aroundtsaid neck, and` having, its

saidy feedhole to deliver screws thereto, the rear end of said magazine being received in said body, air feed passage formedA in, said:A body from said inlet to said magazine, andvalve means positioned to control said feed passage.

Referencesitedin the le of this patent UNITED STATES PATENTS 1,980,967 DeMooy Nov. 13, 1934 2,373,992 Billinghurst Apr. 17, 1945 2,471,793 Stull May 31, 1949 2,534,140 Moore Dec. 12, 1950 2,544,165V Krasnow Mar. 6, 1951 2;605,792. Havener Aug. 5, 1952 2,754,860', Mooreet al July 17, 1956 

